Fluids, such as water, are used in connection with various domestic and industrial applications. As an example, water is used to cool and act as a heat sink for a variety of machinery and in connection with many different industrial processes. As another example, hot water is used to heat buildings and houses.
Aquifers are permeable bodies of rock capable of yielding quantities of water, for example, to wells or springs. Hot dry rock formations are geothermal resources that include subsurface rock structures heated by geothermal energy. Hot wet rock formations are geothermal resources that include subsurface rock structures that contain some moisture or fluid and that are heated by geothermal energy.